This invention relates in general to the segregation of comingles discrete solid substances and more particularly to a process and apparatus for segregating such substances on the basis of vibrations they induce in a sounding plate.
Many processes exist for separating comingled solid substances of relatively small particle size, but most do not possess a high measure of reliability and therefore must be supplemented with visual inspection an expensive and tedious procedure. For example, in the food nut industry, nut cracking machines yield a mixture of nut meat and shell fragments. The former has value as a food product and is packaged and sold. The latter has little value and is often discarded. In any event, to produce a saleable product, the nut meat must be segregated from the shell fragments and any other foreign material. Under current practices most of the separation is achieved with aspirators that withdraw light weight shell fragments and shaker-graders that are actually screening devices which remove most of the high density shell fragments. Even so, the resulting product still contains 10% to 15% shell fragments. This product passes over a so-called picking table where individuals manually pick out the remaining shell fragments as well as any inferior nut meat. This is a tedious procedure and does not afford ample opportunity for those who perform it to concentrate on the quality of the nut meat.